One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant radicchio in Zone 4a can be figured out by referring to the USDA zone info.

Planting Calendar for Radicchio

Frost tolerance for radicchio:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since radicchio are one of those plants that can tolerate a little bit of cold weather you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant radicchio in Zone 4a is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant radicchio and expect a good harvest is probably August. If you wait any later than that and your radicchio may not have a chance to grow to maturity. Starting your radicchio indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Zone 4a the average date of last frost happens on May 15. You can expect an average low temperature of -30°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Zone 4a and it will vary from year to year. Half of the time in Zone 4a there is a last frost after May 15 so make sure that you are ready to cover your radicchio if you have a late frost.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in your other planting guides for Zone 4a.